http://astrolog.org/labyrnth/maze.htm
Under Maze Graphics there are a lot of good ones.
http://astrolog.org/labyrnth/maze/theseus.gif
Even with a spoiler map, the Colossal Cave Adventure takes a while and is interesting to new gamers.
Spoiler: http://www.spitenet.com/cave/ColossalCaveAdventureMap.php
No Clues: http://www.spitenet.com/cave/CCAdventureMapNoClues.php
Play under the pressure of a smart speaker/personal assistant
https://www.amazon.com/teri1337-Colossal-Cave-Adventure/dp/B071WXY4QV
Found on the spitenet page, I haven't tried it but it sounds interesting
$ sudo apt-get update
$ sudo apt-get install colossal-cave-adventure
https://play.google.com/store/apps/details?id=com.ecsoftwareconsulting.adventure430&gl=US
Maze of Twisty Little Passages, all different
The complete graphs of the solution to these mazes interest me, and they are kind of hard to find on google.
https://bluerenga.blog/2011/03/19/adventure-350-points-on-the-worst-maze-ever/
https://bluerenga.files.wordpress.com/2011/03/maze_all_different.pdf
https://bluerenga.blog/2011/03/25/adventure-350-points-best-maze-ever/
https://bluerenga.files.wordpress.com/2011/03/allalike.png
Making a 3d version of these kinds of mazes are interesting to me. Maybe I'll make one in VR or just a 3d game in Unity.